Home networks are utilized to connect devices in the home to one another and to the Internet. These home networks are connected to residential Internet service providers via a device known as a Residential Gateway (RGW). This device provides physical and protocol connectivity between the home network and the access network (i.e., the core network of the Internet service provider including the Internet service provider's access control devices such as a Broadband Remote Access Server (BRAS) router or Broadband Network Gateway (BNG)). In this specification, BRAS and BNG are used interchangeably.
An RGW can provide bridging or routing support for a home network. It typically also provides additional services such as firewall protection and network address translation. The RGW can connect with the devices in a home using both wired and wireless protocols and connections. The RGW can provide a set of Ethernet connections as well as a wireless local area network using IEEE 802.11(a/b/g/n). The RGW can also be a point of service delivery for services such as Voice Over Internet Protocol (VOIP) or de-multiplexing for services like shared television delivery.
An Internet service provider's access control device such as a BNG is also called a network edge device. The BNG is a critical network element for providing Internet services for home networks. The failure of the BNG will make devices in the home networks unreachable by the Internet service provider.